Showing papers on "L band published in 1991"

A Si bipolar 21-GHz/320-mW static frequency divider

Abstract: A silicon bipolar divide-by-eight static frequency divider was developed. A state-of-the-art advanced borosilicate-glass self-aligned (A-BSA) transistor technology that has a cutoff frequency of 40 GHz at V/sub ce/=1 V was applied. Optimum circuit and layout designs were carried out for high-speed/low-power operation. The single-ended input realized by an on-chip metal-insulator-metal (MIM) capacitor makes it easy to use in microwave applications. Ultrahigh-speed operation, up to 21 GHz, was realized, with 320-mW power dissipation from a single +5-V supply. The static frequency divider is a suitable prescaler for phase-locked oscillators (PLOs), completely covering microwave frequencies from L band through Ku band (1-18 GHz). >

A Si wide-band MMIC amplifier family for L-S band consumer product applications

Abstract: By using Si bipolar process technology, medium-power, low-noise and low-power-consumption amplifiers have been successfully realized. For the low-power-consumption amplifier, as little as 4 mA of total supply current is required with 3.4 V supply voltage, 2.3 GHz 3 dB bandwidth and 10.8 dB gain at 1 GHz. >

Wideband characterisation of the high elevation orbit satellite-mobile channel, at L-band

Abstract: An experiment to determine the wideband propagation statistics of the channel at L-band between a high-elevation orbit (HEO) satellite and a mobile unit is described. Channel sounding is accomplished by a spread spectrum beacon on board a light aircraft, together with a receiver located in a ground mobile unit employing a stepped cross-correlation measurement system. Some results of initial measurements are given. >

Characteristics of frequency selective surfaces for a multi-band communication satellite

Abstract: The authors describe an antenna system for a proposed multiband communication satellite utilizing five frequency bands. Ka (30/20 GHz), Ku (14/12 GHz), C (6/4 GHz), S (2.6/2.5 GHz), and L (1.6/1.5 GHz). Seven beam configurations have been created, including three multibeams, three shaped beams, and a circular single beam. The authors present feasibility studies on three kinds of frequency selective surfaces, the key technology for constructing this satellite. One is a novel frequency-selective subreflector with two separate focal feed positions. The others are planar frequency selective surfaces specified with low losses and wide reflection bandwidths. Measured data suggest the reliable achievement of low-loss frequency sharing and the possibility of realizing an advanced communication satellite. >